viii 



in the progress of society, or in questions touching the practical life 

 of men. While busied with researches on abstract principles, he 

 always kept a window open to the outer world : witness his work 

 on Coals, his papers on Currency and Coinage, Variation of Prices, 

 the frequent Autumnal Pressure on the Money Market, and other 

 kindred subjects, and his articles and addresses on questions of the 

 day, published in the " Contemporary," the " Fortnightly Review," and 

 elsewhere. Several of these scattered papers have lately been collected 

 and republished in a separate volume under the title of "Methods of 

 Social Reform;" and a glance at some of the headings will suffice to 

 show the width of Jevons' interest in whatever affects popular pro- 

 gress — Amusements of the People, Free Public Libraries, Museums> 

 " Cram," Trade Societies, Industial Partnerships, Married Women in 

 Factories, Cruelty to Animals, The United Kingdom Alliance, Experi- 

 mental Legislation and the Drink Traffic, State Parcel Post, &c. 



A pamphlet on the Match Tax, which he wrote in 1871, is memorable 

 as a skilful and courageous defence of a most unpopular measure. In 

 his view the country had reached a critical point where "one great 

 and true policy had been nearly if not quite accomplished;" and he 

 feared that " without any strong guiding principle like that of free 

 trade " before it, the nation was in danger of drifting instead of 

 carefully steering in its financial course. " If one-half of the doctrines 

 and arguments which were brought against the Match Tax should be 

 accepted as really true and cogent, the balance of our financial system 

 would be in danger of complete derangement." He therefore con- 

 sidered it important to subject to calm and impartial investigation 

 the various opinions uttered during the heated discussion on the pro- 

 posed new impost, and his pamphlet presents an admirable specimen 

 of the way in which the truths of economics should be applied to 

 questions of taxation. 



But in his "Theory of Political Economy" (1871, second edition 

 enlarged 1879), Jevons dealt not with particular applications, but 

 with the general principles of the science ; he laboured at the founda- 

 tions. Dissatisfied with many of the views of Ricardo and Mill, he 

 sought to construct the science on a new basis. Observing that " as 

 it deals with quantities it must be a mathematical science in matter 

 if not in language," he endeavoured to express quantitatively such 

 notices as utility, value, labour, capital, &c, and he maintained that 

 the employment of mathematical forms is conducive to clearness and 

 precision of expression. It is curious to remark, however, that he 

 did not attempt to develope those forms as a working process, and 

 when it was pointed out to him that a little manipulation of the 

 symbols in accordance with the rules of the differential calculus would 

 often have yielded results which he had laboriously argued out, he 

 contented himself with replying that he did not write for mathe- 



